脑神经胶质瘤细胞癌胚抗原相关细胞黏附分子1对替莫唑胺化疗敏感性的作用及其机制研究

Effect and mechanism of CEACAM1 in brain glioma cells on the sensitivity to temozolomide chemotherapy

摘要:

目的 探究脑神经胶质瘤细胞癌胚抗原相关细胞黏附分子1（CEACAM1）表达对替莫唑胺（TMZ）化疗敏感性的作用及其机制研究。方法 体外培养TMZ耐药人脑神经胶质瘤细胞系U251/TMZ细胞，采用空载质粒或siRNA转染U251/TMZ细胞，分为空载组、TMZ组、siRNA组及siRNA+TMZ组，转染48 h后，GFP荧光检测细胞转染效率。采用实时荧光定量聚合酶链反应检测细胞CEACAM1 mRNA的表达，MTT法检测U251/TMZ细胞增殖，流式细胞术检测细胞凋亡，酶联免疫吸附试验和Western blotting检测Wnt/β-catenin通路相关蛋白的表达。结果 与空载组比较，siRNA组、siRNA+TMZ组CEACAM1 mRNA相对表达量降低（P <0.05），细胞增殖抑制率、细胞凋亡率升高（P <0.05），Wnt1蛋白表达水平、β-catenin及c-myc蛋白相对表达量降低（P <0.05）；与TMZ组比较，siRNA组、siRNA+TMZ组CEACAM1 mRNA相对表达量降低（P <0.05），细胞增殖抑制率、细胞凋亡率升高（P <0.05），Wnt1蛋白表达水平、β-catenin及c-myc蛋白相对表达量降低（P <0.05）；与siRNA组比较，siRNA+TMZ组CEACAM1 mRNA相对表达量降低（P <0.05），细胞增殖抑制率、细胞凋亡率均升高（P <0.05），Wnt1蛋白表达水平、β-catenin及c-myc蛋白相对表达量降低（P <0.05）。结论 CEACAM1表达下调能够抑制脑神经胶质瘤细胞增殖能力，促进细胞凋亡，提高TMZ化疗敏感性，其作用机制可能与Wnt/β-catenin通路有关。

Abstract:

Objective To explore the effect and mechanism of carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) in brain glioma cells on the sensitivity to temozolomide (TMZ) chemotherapy.Methods TMZ-resistant human glioma cell lines U251/TMZ were cultured in vitro and transfected with empty vectors or siRNA, and the cells were thus divided into empty vector group, TMZ group, siRNA group and siRNA + TMZ group. The transfection efficiency was evaluated via fluorescence intensity of GFP at 48 h after the transfection. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the mRNA expression of CEACAM1 in cells. The cell proliferation and apoptosis were measured via the MTT assay and flow cytometry, respectively. ELISA and Western blotting were applied to determine the expressions of proteins associated with the Wnt/β-catenin pathway.Results Compared with the empty vector group, the mRNA expressions of CEACAM1 were lower, the rates of cell proliferation inhibition and apoptosis were higher, and the protein expressions of Wnt1, β-catenin and c-myc were lower in the siRNA group and the siRNA + TMZ group (P < 0.05). Compared with the TMZ group, the mRNA expression of CEACAM1 was lower, the rates of cell proliferation inhibition and apoptosis were higher, and the protein expressions of Wnt1, β-catenin and c-myc were lower in the siRNA group and the siRNA + TMZ group (P < 0.05). Compared with the siRNA group, the mRNA expression of CEACAM1 was lower, the rates of cell proliferation inhibition and apoptosis were higher, and the protein expressions of Wnt1, β-catenin and c-myc were lower in the siRNA + TMZ group (P < 0.05).Conclusions Down-regulation of CEACAM1 can inhibit the proliferation of brain glioma cells, promote cell apoptosis, and increase the sensitivity to temozolomide chemotherapy, the mechanism of which may be related to the Wnt/β-catenin pathway.